/*
 Copyright (C) 2021 Eric Wasylishen

 This file is part of TrenchBroom.

 TrenchBroom is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 TrenchBroom is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with TrenchBroom. If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

#include <QObject>

#include <chrono>

class QTimer;

namespace tb::ui
{

/**
 * Helper for delaying actions until control returns to the Qt event loop, and coalescing
 * multiple requests.
 */
class SignalDelayer : public QObject
{
  Q_OBJECT
private:
  QTimer* m_timer = nullptr;

public:
  explicit SignalDelayer(std::chrono::milliseconds delay, QObject* parent = nullptr);
  explicit SignalDelayer(QObject* parent = nullptr);

public slots:
  /**
   * Enqueues an action on the Qt event loop that will emit `processSignal()`.
   *
   * Multiple calls to `queueSignal()` before the signal is emitted will only emit one
   * `processSignal()`.
   */
  void queueSignal();

signals:
  void processSignal();
};

} // namespace tb::ui
